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<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <!-- <button onclick="alert('hello world')">按钮</button> -->
  <!-- <button>按钮2</button>
  <script>
    document.querySelector('button').onclick = function() {
      alert('轻轻挂在树上许个愿')
    }
  </script> -->
  <button>按钮3</button>
  <script src="./scripts/test.js"></script> 
</body>
</html>